What consequence can improper gear selection lead to while driving downhill?

Improper gear selection while driving downhill can lead to a loss of engine braking, which is a critical safety feature when navigating steep grades. Engine braking occurs when the vehicle's engine is used to help control speed, particularly when moving downhill. By selecting the appropriate gear, the engine can slow the vehicle down, reducing reliance on the brakes. This is crucial because excessive use of brakes can lead to overheating and diminished braking power, increasing the risk of losing control of the vehicle.

When a driver chooses too high of a gear while descending a hill, the engine may not provide sufficient resistance to counteract the vehicle's momentum. This can result in the vehicle accelerating uncontrollably, leading to dangerous situations such as skidding or crashing. Therefore, correctly selecting a lower gear is essential for maintaining control and ensuring safe braking capability when driving downhill.

The other choices, while potentially related to driving conditions, do not address the critical aspect of maintaining control through appropriate gear selection.